Energy-efficient resource allocation for hybrid bursty services in multi-relay OFDM networks

Abstract

Abstract-In this paper, we propose Mapped Two-way Water Filling (MTWF) scheme to maximize Energy Efficiency (EE) for hybrid bursty services with Quality of Services (QoS) requirements in Two-Way Multi-Relay (TWMR) OFDM networks. The bursty traffic is first analyzed by strictly proved equivalent homogeneous Poisson process, based on which the QoS requirements are converted into sum-rate constraints. The formulated non-convex EE maximization problem, including subcarrier assignment, Relay Selection (RS) and rate allocation, is NP-hard involving combinatorial optimization. To conduct optimal RS on each subcarrier without priori bursty traffic knowledge, we utilize some approximate relationships under high data rate demands to remove its dependence on two-way data rates, and simplify the whole optimization problem as well. After the optimal channel configuration is obtained, which only depends on channel conditions, subcarrier assignment is attained through Elitist Selection Genetic Algorithm (ESGA), and rate allocation of each service is fulfilled by deducing two-way water filling principle. A new equivalent optimization objective function is proposed next as the simple evaluating index in ESGA to reduce complexity. Finally, simulations are carried out to verify the superiority and convergence of our scheme, as well as the applicability for different scenarios.

Energy Efficiency Analysis of Heterogeneous Cellular Networks With Extra Cell Range Expansion

“…where G B = GB = G 1 and f G l is obtained by Lemma 2. Using (5), the CDF of the SINR of the user with the distance of G B can be formulated, as given by…”

“…Therefore, the architecture of multi-tier heterogeneous cellular network (HCN), based on small cells, has been proposed as a promising technology to increase the network capacity and avoid coverage holes [3]. Moreover, due to the rapidly growing energy consumption in wireless networks, the research of EE has attracted wide attention all over the world [4], [5]. It is known that HCN with small cells can solve the physical scarcity of radio frequency and increase the system capacity to some extent, but at the cost of deploying more hardware infrastructures, which leads to higher energy consumption consequently [6], [7].…”

Congestion probabilities in OFDM wireless networks with compound Poisson arrivals

“…The motivation behind this work is to study, at call‐level, the case of bursty traffic in orthogonal frequency division multiplexing (OFDM) networks. Although bursty traffic does appear in OFDM networks as various papers show [9–13], there are no efficient analytical models in the literature used to determine and evaluate the QoS parameters such as CBP and network resources utilisation. To this end, we approximate bursty traffic via the compound Poisson traffic and study the downlink of an OFDM‐based cell that accommodates calls from many service‐classes with various QoS requirements.…”